I think the following:
1. Have the mercs be able to jump a little higher, so they can at least get up a 2-foot wall. (even I can jump even higher, like 3-feet in the air)
2. Fix the grapple's look when it is attached to something, and have it pull you straight towords your target, not drag you on the ground until you jump, ect.
3. Mercs need some way, other than the jetpack, to get the jedi away from them. Add like a simple 1-button push that does like a kick or add a force power that stuns, or blinds the jedi for like 6 seconds so he/she can get away.
There you have it.